There seems a logical glitch in the above video: at 4:16, Sabine said that Dirac found the solution always come in pairs, which would logically entail the 1:1 ratio since it is said in the existing theory that there was no matter and antimatter particles but only pure energy (meaning photons?) at the beginning....but at 8:40 Sabine says that Dirac did not predict a 1:1 ratio and we need to give an initial condition........
If Sabine is right here, then the current theory that there was no matter and antimatter at the beginning would be wrong.....the theory should not start with pure energy, but start with some number of matter particles at the beginning, which seems to invalidate the current theory....